Electric connector



April 9, 1957 s. N. BUCHANAN 2,788,508

' ELECTRIC CONNECTOR Filed Jan. 6, 1955 3 Sheets-Sheet l April 9, 1957 s. N. BUCHANAN 2,788,508

ELECTRIC CONNECTOR Filed Jan. 6, 19s; a Shets-Sheet 2 April 9, 1957 s. N. BUCHANAN ELECTRIC CONNECTOR 3 Sheets-Sheet 5 Filed Jan. 6, 1953 INVENTOR.

United States Patent O ELECTRIC 20NNECTOR Stephen N. Buchanan, Westmoreland, Md., assignor to Buchanan Electrical Products Corporation, Hii lSidil, N. 1., a corporation ofNcw Jersey .Applicationf January 6,.195,3,"Serial No. 329,867

3 Claims. (Cl. 339 276) lThis invention-relates toelectrical equipment and more particularly to electric .connectorsof the type that are secured to electrical conductors by crimping a conductor-receiving portion of the connector onto the hated wires of 1 a conductor.

Connectors of this general classification usually have extendingfrom the. conductorereceiving portion, a terminal engaging-portion for attaching one-end of the connector toaterminaLYbindingpost or-the like, and are known to thoseversedin-jthe art as terminal lugs. The connectors, when they aremechanically attached to a conductorin the manner mentioned above, provide a path for the, flow of current between-the conductor and a terminalor binding postthat may be connected to the terminal engagingportion of theconnector. Because the connector must conduct current from the conductor to the binding post, it is necessary that they be manufactured from a .material having :a i high thermal conductivity. Copper and copper base-alloys are two such materials thatexhibit this characteristic.

An important object of this invention is to provide an improved electric connector of the crimp-on type, which connector is of inexpensive and simple construction.

Various other objects 'ofthe-invention will be apparent from the ensuingdescriptionandanginspection ofaccompanying drawings, in which:

Figs l throughSillustratethe stockat successive stages of fabrication of -the connector;

Fig. 6 illustrates the completed connector;

Figs-'7 through'9 are plan-views in section showing the relative position of the forming slides during the first operation;

Fig. 10 is a perspective view of the forming slides and arbor during the first operation;

Figs. 11 and 12 are views in perspective of the second operation wherein the conductor engaging portion of the connector is fabricated;

Figs. 13 and 14 illustrate in perspective the relative position of the forming members as the terminal engaging portion of the connector is fabricated and as the restraining sleeve is assembled on the connector; and

Fig. 15 is a perspective view of the assembled connector in completed form, as it leaves the last operation.

Briefly, the invention comprises a novel electric connector that includes a conductor-receiving portion and a terminal engaging portion integral therewith. These connectors are adapted to be secured upon an electrical conductor by crimping the conductor-receiving portion into intimate contact with the conductor. The terminal engaging portion may then be attached to a binding post or any other connector. The three elements, conductor, connector and binding post, are then joined mechanically and electrically. A method for manufacturing such a connector involves fabricating a length of common wire by bending the wire into a conductor engaging portion and a terminal engaging portion and inserting a hollow 2 sleeve overthe conductor .iengaging portionto-formsan enclosure for the conductor.

One manner of practicingthe method ofmakingaa terminal lug type of connector fromjaxstr ip of copper wire involves theuse of a multi-slide =wireformingrnachine including a plurality of reciprocating slides that act upon a strip ofv copper wire in iaxpredeterminedwtimed sequence so asto form thewire into the connector. FA quantity of wire is preferably disposed on a 5 spool; (not shown) adjacent a conventional feeding'rlevice. Thenvire is fed by the feeding device into the 'WiIQU'fOIIIIiDgTmH- chine and into the .pathof afirst reciprocatinggslide member it} as clearly shown inFig. 7. -As thetforernost end of the wire engagesthe pressure-sensitive.surfacerof .stop member 12, the first of .a series :offforming steps is initiated when arbor member.14.having..-a movable sleeve 16 mountedthereon moves axiallydownward-to a position contiguous to the wire and is received in a movable ring 18. The reciprocatingslide member 10 then moves from its inoperativewposition' as shown in Fig. 7 to its extended position as shown in Figure :8. "As slide member 311-0 moves forward, cutter -bar 20 attached to one side of member 10 severs a predetermined length of wire from the continuous strand being fedginto the machine. The leading edge of slide 10; has a,recess;22;of a depth equal to the. diameter of the wire landadaptedtto accommodate the wire astheslidemoves-forward. fS-lide member 10 is also provided with anotch 24' for receiving the arbor 1-4. ,As the reciprocating slide .member moves through one cycle of its operation, a length -of wire :18 severed I and "bent pr formed. into a; u s hape about the arbor member 14ersshown in Eig.-.8.

The next'formingtstep is accomplished byca pair of reciprocating slides 26 and 28, moving-1intopposed -direo tions or to and from each .other. 'These platter :slides move ina path normal tothe direction OfyHlDYCIHQIlLOf slide member 14 and are provided in their leading edges with wire receiving recessesfit) rand,32 similaritoiand coplanar with recess 22. The recess 30:.is ofa depth equal to the diameter of the wireand comprises astraight portion 34 which is normal to the-directions,of,movementof the slide member lfi and a -connectedg arcuate portion 36 which at its bottom subtends slightly vless than .90 degrees. The recess 32visa mirror imagenofgthe recess 30. 1 Corresponding .portions :38 :and 1.40 .are disposed on cqmplementary slide:mernberzZS. sAs thesIides move toward each other, they engage the parallel legs of the Ushaped wire and force them into a juxtaposed relation with portions of the legs forced into intimate contact with the arbor member, as shown in Fig. 9. At-

tention is also directed to Fig. 10 which illustrates in perspective the relative position of the forming members at this stage of the process.

The wire now has been formed into two portions, one circular, the other rectilinear and extending radially from the circular portion. The rectilinear portion cooperates (after further fabrication), in a manner to be later described, with a hollow sleeve member to form a conductor engaging enclosure while the circular portion normally is attached to a terminal, binding post or like electrical connection.

The configuration of the wire as produced by the above forming operation is in general maintained throughout the remaining operations. The next step involves coining the connector and ofisetting the terminal engaging portion from the conductor engaging portion. Prior to this forming step the complementary slides 26 and 28 retract to their inoperative positions as illustrated in Fig. 8, with the wire and slide member 10 as shown in Fig. 9. A section 42 of the base member, upon which the complementary slides 26 and 28 are supported is vertically movable and cooperates with a vertically movable punch member 44 to perform the next step. A notch 46, semi-circular in section, is located in the surface of member 42 in alignment with the conductor engaging portion of the connector. n the face of the punch 44 is a boss 48, also in alignment with the conductor, and adapted to complement the notch as the members 42 and 44 forcibly converge upon the connector. As a result of the engagement of punch member 44 and the die block 42, the conductor engaging portion of the connector becomes semi-circular in section. It may also be desirable to provide the outer surface of the boss 48 with a series of ridges so that the inner surface of the connector will more readily grip a conductor when the connector is united therewith.

The next step involves offsetting the arcuate or terminal engaging portion of the connector from the rectilinear or conductor engaging portion as mentioned above. During this step the reciprocating slide reverts to its inoperative position and the connector is held between members 42 and 44. Sleeve members 16 and 18 are then moved downwardly and upwardly respectively. The circular portion of the connector is engaged by the sleeve 16 and forced against the upper surface of the sleeve 18 in a plane parallel to but slightly below the plane of the conductor engaging portion held between members 42 and 44. The connector now has the configuration illustrated in Fig. 5.

In order to apply the metallic restraining sleeve 50 to the conductor engaging portion of the connector, the members 42 and 44 separate while the sleeves 16 and 18 dwell in the position shown in Fig. 13. The purpose of the restraining sleeve 50 is to form an enclosure for the conductor and prohibit the juxtaposed legs of the connector from separating. One manner of assembling the sleeve and the connector comprises placing the sleeve onto a spring loaded pin 52 afiixed in a bore in the end of a travelling arbor 54. The sleeve 50, having been hopper-fed onto the pin 52, has an inside diameter substantially equal to the outside diameter of the conductor engaging portion of the connector and has its leading edge slightly flared. As the fore end of the pin strikes the connector, continued movement of the arbor strips the sleeve from the pin and moves it into a frictional fit with the outer surface of the conductor engaging portion of the connector. To prevent sleeve 50 from thereafter becoming separated from the remainder of the connector, sleeve 16 and ring 18 may be provided with stop elements 56 so shaped as to distort portions in the leading edge of the sleeve 50 into contact with the conductor receiving portion of the connector, as shown in Fig. 6.

After the sleeve 50 has been placed on the connector, arbor 14, with sleeve 16 thereon, retracts to its inoperative position clear of sleeve 18 as shown in Fig. 15 and the assembled connector is removed by a blast of air from a conventional air hose (not shown).

Other connectors, varying in shape, may be produced by the same method as described above.

As many changes will occur to those skilled in the art, the details of the disclosed connector are not to be taken limitations upon the invention except as those details may he inciuded in the appended claims.

I claim:

1. An electric connector adapted to be crimped onto an electric conductor, comprising a first piece including a trough-like part having first and second coaxial cylindrical segments having adjacent edges abutting each other parallel to said axis, said segments together being less than 360 degrees in circumferential extent and a loop for engaging a terminal, said loop having first and second ends integral respectively with said first and sec ond segments, and a second piece including a sleeve embracing and in frictional engagement with said troughlike part and holding said adjacent edges together, said sleeve and said trough-like part together providing a conductor-receiving opening.

2. The invention set forth in claim 1 in which said sleeve has an indentation providing an area of increased frictional engagement with said trough-like part.

3. The invention set forth in claim 1 in which said sleeve has first and second indentations providing areas of increased frictional engagement with said trough-like part, said first and second indentations located at the end of said trough-like part adjacent said loop and spaced the same circumferential distance from said abutting edges.

References Cited in the file of this patent UNITED STATES PATENTS 1,537,728 Bagby May 12, 1925 1,610,052 Holmes Dec. 7, 1926 1,936,611 Young Nov. 28, 1933 2,106,007 Klein Jan. 18, 1938 2,358,745 Stieglitz Sept. 19, 1944 2,452,932 Johnson Nov. 2, 1948 2,554,813 Buchanan May 29, 1951 2,685,076 Hoffman July 27, 1954 2,697,213 Patton Dec. 14, 1954 2,724,098 Bergan Nov. 15, 1955 

